1. Field
The invention relates to an access multiplexer for multiplexing Internet Protocol packets to be exchanged between a network device and a subscriber device, the Internet Protocol packets being encapsulated, between the network device and the access multiplexer, in first packets comprising first encapsulations and, between the subscriber device and the access multiplexer, in second packets comprising second encapsulations.
2. Description of Related Art
A prior art access multiplexer is of common general knowledge. Such an access multiplexer couples a network device and a subscriber device with each other and allows an exchange of Internet Protocol packets between the network device and the subscriber device in two directions. In a first direction, for example from network device to subscriber device, at the network device the Internet Protocol packets are encapsulated via first encapsulations, at a network side of the access multiplexer the Internet Protocol packets are decapsulated, at a subscriber side of the access multiplexer the Internet Protocol packets are encapsulated via second encapsulations, and at the subscriber device the Internet Protocol packets are decapsulated. In a second direction, for example from subscriber device to network device, at the subscriber device the Internet Protocol packets are encapsulated via the second encapsulations, at a subscriber side of the access multiplexer the Internet Protocol packets are decapsulated, at a network side of the access multiplexer the Internet Protocol packets are encapsulated via the first encapsulations, and at the network device the Internet Protocol packets are decapsulated.
The known access multiplexer is disadvantageous, inter alia, owing to the fact that it does not allow routing protocols which use multicast Internet Protocol destination addresses or broadcast Internet Protocol destination addresses to be run transparently between the network device and the subscriber device. Instead, in the prior art, the access multiplexer terminates such routing protocols, leading to a situation where the routing protocols are respectively terminated and instantiated in the access multiplexer. A first instance runs between the network device and the access multiplexer where it is terminated and a second instance runs between the access multiplexer and the customer device. Examples of such routing protocols are the Routing Information Protocol and the Open Shortest Path First Protocol.